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POGroup by weekdays with Core Data
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  1. POGroup by weekdays with Core Data
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    copied!<p>In my Core Data Model i've got an entity that has a date attribute and as the title suggests, i'd like to group this entity by (week)days.</p> <p>The problem is, the dates are stored more or less as timestamps and i don't know how to create a predicate that is capable of grouping/filtering my entities approprioately.</p> <p>I've figured out that i will probably have to do a fetch for each day, so created following method. The code were i need help with is right in the middle of it.</p> <pre><code>- (NSFetchedResultsController *)fetchedResultsController:(NSDate *)day { if(fetchedResultsController != nil) return fetchedResultsController; // Create and Configure Request NSFetchRequest *request = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:entityName inManagedObjectContext:managedObjectContext]; [request setEntity:entity]; // Predicate // pseudo code where i'm clueless is marked by "&lt;" and "&gt;" - start NSPredicate *predicate = [NSPredicate predicateWithFormat:@"DateAttribute BETWEEN &lt;first second of day&gt; AND &lt;last second of day&gt;"]; // or NSPredicate *predicate = [NSPredicate predicateWithFormat:@"&lt;dayofmonth-month-year of DateAttribute&gt; LIKE &lt;dayofmonth-month-year of day&gt;"]; [request setPredicate:predicate]; // pseudo code where i'm clueless is marked by "&lt;" and "&gt;" - end // Sort descriptors NSSortDescriptor *titleDescriptor = [[NSSortDescriptor alloc] initWithKey:sortDescriptorName ascending:YES]; NSArray *sortDescriptors = [NSArray arrayWithObject:titleDescriptor]; [request setSortDescriptors:sortDescriptors]; // create and init fetchResultsController NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:request managedObjectContext:managedObjectContext sectionNameKeyPath:nil cacheName:@"Root"]; self.fetchedResultsController = aFetchedResultsController; fetchedResultsController.delegate = self; //Memory [request release]; [titleDescriptor release]; [aFetchedResultsController release]; return fetchedResultsController; </code></pre> <p>}</p> <p>I'd really appreciate any help. Thanks</p>
 

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